1. Field of the Invention
The present invention generally relates to gear motor assemblies and control systems and, in particular, to a gear motor assembly and control system for use with ice dispensers, crushers and other similar devices. The assembly utilizes a novel reversing circuit which allows the use of a bidirectional DC powered gear motor in existing refrigerator and freezer configurations, which heretofore used unidirectional AC powered gear motors, to power and control ice crushing and dispensing apparatus.
2. Description of the Related Art
Electromechanical devices such as ice crushers and ice dispensers in freezers and refrigerators are often powered by small motors that take the form of gear motors. With the continuing objective of minimizing the size of such motor assemblies, it has been a constant struggle to design a motor assembly for use with such devices that not only produces the required high torque output but that makes efficient use of the space within the devices.
Many freezer and refrigerator manufacturers configure their product's electrical systems for unidirectional AC gear motor and solenoid assemblies to accomplish the ice crushing or ice dispensing cycle. FIG. 1 shows a typical electrical control system of an ice delivery mechanism utilizing a unidirectional AC shaded pole gear motor M and an AC solenoid S1. During an ice dispensing cycle L1 (115 V, approximately 300 watts) is energized powering the shaded pole motor and cubed ice is dispensed. During an ice crushing or shaving cycle, L1 is powered and L2 (115V, approximately 30 watts) is also powered to engage the solenoid (typically when the solenoid is powered a mechanical element such as a knife is engaged to crush or shave the ice).
It is desirable to incorporate a solid state DC gear motor control system into existing refrigerators or freezers without having to change the basic electrical wiring within the refrigerators or freezers. The unidirectional AC powered gear motors heretofore used require additional mechanical elements (engaged by the solenoid) to crush or shave ice. The AC gear motors also require high voltage, double pole, double throw relays, and are more expensive and less reliable than solid state DC controls. The present invention provides a novel solution to address these problems.